Fluid dispensing nozzle and latchpin therefor

ABSTRACT

A fluid dispensing nozzle for dispensing gasoline wherein a high-level shut-off means includes a pressure-sensitive diaphragm, a latch pin carried by the diaphragm, a tapered camming surface on the latch pin, and means releasably engaging the camming surface for establishing a pivot point for a valvecontrolling lever. The tapered portion is formed as a rotatable sleeve on the latch pin.

Unite States Patent [1 1 Carder Sept. 11, 1973 1 FLUID DISPENSING NOZZLE AND LATCHPIN THEREFOR [76] Inventor: Mervin L. Carder, P.O. Box 3725, 509 N. Geyer Rd., Kirkwood, Mo. 63122 [22] Filed: Nov. 11,1971

121] Appl. No.: 197,730

[52] U.S. Cl 141/225. 29/401, 137/315 51 int. CI ..B65b 57/06 58 Field of Search 141/39, 214, 22s,

l4l/l92213, 215-224, 226-229; 74/567; 70/34, 386; 137/624.27, 315; 251/94; 29/157 C, 401

[56] References Cited UNITED STATES PATENTS Schaub et al. 29/401 Primary Examiner-John Petrakes Assistant ExaminerFrederick R. Schmidt Att0rneyJ. Philip Polster [57] ABSTRACT A fluid dispensing nozzle for dispensing gasoline wherein a high-level shut-off means includes a pressure-sensitive diaphragm, a latch pin carried by the diaphragm, a tapered camming surface on the latch pin,

and means releasably engaging the camming surface for establishing a pivot point for a valve-controlling lever. The tapered portion is formed as a rotatable sleeve on the latch pin.

14 Claims, 5 Drawing Figures 1 FLUID DISPENSING NOZZLE AND LATCHPIN THERE-FOR BACKGROUND OF THE INVENTION This invention relates to a dispensing nozzle of the 5 I type used to dispense gasoline and has particular application to a type of nozzle having a high-level shut-off utilizing a particular latching mechanism. As is well known, gasoline dispensing nozzles include a casing having a main valve, a manually operable lever, and an automatic high-level shut-off means which forms a pivot for the lever. Upon filling of a gasoline tank, the automatic shut-off allows the pivot point to shift, thereby allowing the main valve to close. The general type of dispensing nozzle to which this invention may be applied is shown in US. Pat. No. 2,582,195 to L.H. Duerr, and is also shown in a widely used commercial form in U.S. Pat. No. 3,540,496 to M.C. Myers. The

type of automatic shut-off disclosed in these patents includes a cylindrical plunger slidably mounted 'm the nozzle casing. The lever is pivoted to the lower end of the plunger. At the upper end of the plunger a plurality of latching balls are carriedwithin radial openings in the plunger for radial movement toward and away from the axis of the plunger. These balls engage an annular shoulder in the casing and hold the plunger in a raised position when they are urged radially outwardly by a cooperating tapered cam surface on a latch pin extending into an axial bore in the plunger. The upper end of the latch pin is secured to a diaphragm which forms the lower wall of a pressure chamber in the nozzle housing. A passage from this chamber to a point near the outlet end of the nozzle permits air to be drawn into the chamber as air is drawn out of it by a Venturi in the gasoline flow passage through the nozzle, so long as the outlet end of the nozzle is open to the atmosphere. When the end of the nozzle is immersed in gasoline, the suction from the Venturi evacuates the pressure chamber, and causes the diaphragm to pull the latch pin from the plunger. The latching balls in the plunger then move radially inward andallow the plunger to drop.

The automatic shut-off system described has the advantage over certain other such systems that the latch pin is unlikely to become stuck in the plunger, a failure which would prevent the automatic shut-off system from releasing the operating lever of the nozzle. However, the conditionand taper. of the camming surface on the latch pin are extremely important to the successful operation of the automatic shut-off system. To assure the proper taper and surface condition of the camming surface, the latch pin is carefully machined. In use, the camming surface slowly deteriorates, and the reliability of the nozzle correspondingly deteriorates.

A gasoline dispensing nozzle has a relatively short operating life during which it operates reliably. Thereafter, the nozzle is commonly rebuilt by either replacing or reworking some of the operating parts. In this process, reworking of the latch pin has required substantial skill and time, and has been one of the most likely sources of malfunction in the rebuilt nozzle.

SUMMARY OF THE INVENTION One of the objects of this invention is to provide a gasoline dispensing nozzle which is longer lived than comparable presently known nozzles.

Another object is to provide such a nozzle which is easier to build and easier to rebuild than presently known nozzles.

Other objects will occur to those skilled in the art in light of the following description and accompanying drawings.

In accordance with this invention, generally stated, a gasoline dispensing nozzle of the type which includes a casing having an inlet and an outlet and a passage therebetween, a main valve in the passage biased to a closed position, a manually operable lever for opening the main valve, and an automatic shut-off device including a pivot for the lever and means responsive to submersion of the outlet end of the passage for shifting the pivot is provided which includes an improved latching means for the automatic shut-off means. The automatic shut-off means includes the usual slidable plunger, latching balls mounted in radial holes in the plunger, a latch pin extending into an axial bore in the plunger and a diaphragm secured to the latch pin for moving the latch pin from a position in the plunger bore for holding the latching balls radially outwardly against a shoulder in the casing upwardly away from the axial bore to allow the latching balls to move radially inwardly, thereby allowing the plunger to drop. It also includes the usual pressure chamber above the diaphragni, aspirating means for withdrawing air from the pressure chamber and means balancing the pressure in the pressure chamber so long as the oulet portion of the nozzle is not submerged. In accordance with this invention, the latch pin includes a tapered (frusto-conical) camming surface which is formed as a sleeve on the latch pin. The sleeve is freely rotatable and tends to rotate to provide even wear on the sleeve in use. The sleeve is preferably made of hardened steel, but the remainder of the pin may if desired be made of other materials such as plastic. The latch pin of this invention may thus be inexpensive to manufacture, and is also capable of being rebuilt at low cost. The body of the pin may be cast rather than machined and the sleeve may be formed by known metal forming techniques other than machining if desired. When necesary, the sleeve may be replaced rather than reworked, with a substantial saving in time, labor and ruined parts.

It has been found that the present commercial practice of utilizing cast plastic plungers such as the plunger 34 in the Myers patent (No. 3,540,496) which are not free to rotate, rather than the earlier used rotatable plunger shown for example in C.V.M. Sutcliffe et al., U.S. Pat. No. 3,020,940, has resulted in the wearing of grooves in the cam surface of the latch pin. However, by use of the rotatable sleeve of this invention, the wear on the sleeveisgenerally uniform. The present inven tion is therefore particularly advantageous when used with the newer form of plunger.

BRIEF DESCRIPTION OF THE DRAWINGS A In the drawings, FIG..1 is a view in side elevation, partially broken away, of a gasoline dispensing nozzle embodying the present invention;

FIG.'2 is a view in side elevation of the disassembled DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, and in particular to FIG. 1, reference numeral 1 indicates a fluid dispensing nozzle embodying the present invention. The nozzle 1 includes a casing 3 having a passage through it including an inlet 5 and an outlet 7. Inlet 5 is threaded to receive a flexible hose or the like from a gasoline pump and the outlet 7 includes a spout adapted to be inserted into the fill tube of a gasoline tank. A main poppet valve 9 is urged by a spring 11 against a cooperating valve seat 13 to close the passage through the casing 3.

A stem 15 extending from the lower end of the valve 9 is slidably mounted in the casing 3. The lower end of the stem 15 is engaged by a manually operable lever 17 which is normally suitably pivoted to lift the main valve 9 from its seat 13 when the lever 17 is lifted. The fully open position of the lever 17 and valve 9 is shown in solid lines in FIG. 1. A hold-open clip 19 is pivoted at its upper end to a cast hand guard 21 and is spring biased rearward out of engagement with the lever 17. Fingers 23 on the clip 19 are so shaped that downward pressure of the lever 17 (caused by the spring 11) holds the clip 19 in its forward position.

The forward end of the lever 17 is held by a pivot pin 25 t0 the lower end of a plunger 27. The plunger 27 forms a part of an automatic shut-off system for shutting off all flow of gasoline through the nozzle when the gasoline in the tank being filled reaches a predetermined level.

The automatic shut-off system includes the plunger 27, a latch pin 29, three latching balls 31, a diaphragm 33, a Venturi means indicated generally at 35, and a tube 37. The plunger 27 is now conventionally made of molded plastic. An acetal resin, such as the homopolyme'r materialsold by E. I. DuPont de Nemours & Company, Inc. under the trade name Delrin," is preferred because of its low coefficient of friction, dimensional stability and resistance to attack by gasoline. A coil spring 39 biases the plunger 27 upwardly.'The latch pin 29 extends into an axial bore 41 in the upper end of the plunger 27. Three radial openings 43 extending from the outer surface of the cylindrical plunger 27 into the axial bore 41 act as guideways for the latching balls 31. An annular stop 44 on the lower end of the plunger limits its upward motion. The latch pin 29 includes a stop section 45 in the form of a hex nut, a cylindrical section 47, a tapered (i.e., frusto-conical) camming section 49, a more severely tapered transistion-section 51 and an elongate guide section 53. The taper section preferably has a taper of about 4 56. The elongate guide section 53 is now eliminated or greatly reduced in length on many commercial latch pins, as shown for example in Myers U.S. Pat. No. 3,540,496. An axial tap at the upper end of the latch pin 29 is provided for attachment of the latch 29 to the diaphragm 33 by a screw 55. The diaphragm 33 is secured around its periphery to the casing 3 by a cap 57, and defines with the cap 57 a pressure chamber 59 in the casing. The pressure chamber 59 communicates through a passage 61 with the Venturi means 35. The chamber 59 also communicates through a passage 63 and tube 37 with an aperture 65 in the spout 7 near the open end of the spout 7. A balance spring 67 is provided on the upper side of the diaphragm 33 for positioning the latch pin (hence the camming section 49) and for determining the sensitivity of the automatic high level shut ofi system.

The construction and operation of the gasoline nozzle as thus far described is conventional and its operation is well known. Briefly, when the lever 17 is in its normal released position, the main valve 9 is closed, the plunger 27 is held by spring 39 in the uppermost position permitted by the plunger stop 44, the diaphragm latch pin 29 is urged downwardly, so that its stop section 45 rests on the top surface of the plunger, by balance spring 67, and the latching balls are allowed a slight amount of radial play between the latch pin camming surface 49 and an inner cylindrical wall of the casing 3. When the lever 17 is raised to the position shown in solid lines in FIG. 1, plunger 27 moves downward a short distance to the position shown, in which balls 31 are held radially outwardly against a downwardly inward sloping shoulder 69 in the casing 3 by the camming section 49. The plunger 27 thus is held in its upper, latched position by latching balls 31. Latch pin 29 is held in its latching position shown in FIG. 1, by the balance spring 67 and by the relative pressures above and below the diaphragm 33. The flow of gasoline through the Venturi 35 draws air through the flow passage consiting of aperture 65 in the nozzle, tube 37, pressure chamber 59 and passage 61. When the level of gasoline in the tank or other vessel being filled reaches the level of the aperture 65, pressure in the chamber 59 is reduced and the diaphragm 33 rises to the position shown in dotted lines in FIG. 1. The latch pin 29 is thereby lifted from its latching position and the latching balls 31 are urged by the shoulder 69 radially inward to the position shown in dotted lines. The plunger 27 is thereby released from its latched position and drops to the position shown in dotted lines, under the influence of spring 11, which also closes the valve 9. In the lower position of the plunger 27, the lever 17 cannot contact the valve stem 15. This automatic closing action occurs whether the lever 17 is held by hand or by clip 19. If the clip 19 has held the lever 17, it is released automatically when the downward pressure of spring 11 is removed.

The novel latch pin of this invention utilized in the nozzle 1 is shown in more detail in FIGS. 2-5. In one embodiment, shown in FIGS. 2-3, the latch pin 29a is made of hardened steel, as are presently known latch pins. The hexagonal nut stop section 45, cylindrical spacer section 47 and guide rod section 53 are all conventional, as is the axial tap at its upper end. However, the tapered section 494 is formed as a separatehardened steel sleeve joumaled on a cylindrical bearing section 71 of the pin body. A snap ring 73 held inan annular groove 75 at the upper margin of the severely tapered transistion section 51a acts as a retainer for the sleeve 49a. I

It has been found that the improved latch pin of FIGS. 2-3 provides for longer and more reliable operation than conventional latch pins. It is believed that the improved operation is in part due to rotation of the sleeve 49a, which reduces the susceptibility of its surface to pitting or other types of wear by the latching balls '31. In some previously known nozzles, the plunger section was cast of metal and was rotatably connected to the manually operable lever by a yoke section. This arrangement also caused somewhat less wear to the camming surface of the latch pin, but was expensive and led to greater wear of other parts than does the presently used Delrin plunger.

In the manufacture of the pin 29a, the pin body and the tapered camming sleeve may each be formed on a simple screw machine. The sleeve may be rolled on the same device on which it is machined. Therefore, the need for careful grinding of the camming surface to close tolerances is no longer required. Of course it may be polished by presently used methods. When the camming surface eventually becomes worn, thereby impairing operation of the nozzle, the sleeve 49a is easily and inexpensively replaced. Therefore, one of the most difficult operations in rebuilding a nozzle is eliminated without requiring the purchase of a relatively expensive latch pin.

The latch pin of this invention has the further advantage in use that the absolute dimensions, as well as the taper, of the camming portion of the pin are easily and precisely controlled. Heretofore, it has frequently been necessary to vary the size or weight of the diaphragm balance spring 67 to provide proper sensitivity of the automatic shut-off system, to compensate for slight variations in the size of the camming section 49. The nozzle of this invention, utilizing the latch pin of this invention, may utilize a spring of a standardized size and weight and still provide satisfactory sensitivity.

Another embodiment of latch pin of this invention is shown in FIG. 4-S. In this embodiment, the body of the latch pin 2% is cast of a thermal plastic material. An acetal resin, such as the homopolymer material sold by E. l. DuPont de Nemours & Company, Inc. under the trade name Delrin, is preferred because of its low coefficient of friction, dimensional stability and resistance to attack by gasoline. The shape of the pin 2% is the same as that of the pin 2% shown in FIGS. 2-3, except that the tapered transistion section 51a has been replaced by a cylindrical step section 77. A tapered camming sleeve 49b is journaled for rotation on a bearing section 71b and is retained axially by a more severely tapered retainer 51b press fitted onto the step section 77. This embodiment has all the advantages of the pre vious embodiment except that the sleeve 49b is less easily replaced. It has the additional advantage that it is far less expensive to manufacture to close tolerance because no machining or grinding is needed to form the body part. Furthermore, because of its light weight, it is somewhat more easily withdrawn by the diaphragm 33, therefore making the automatic shut-off system somewhat quicker responding.

Numerous variations in the dispensing nozzle and latch pin of this invention, within the scope of the ap pended claims, will occur to those skilled in the art in light of the foregoing disclosure. For example, the configuration of the latch pin may be somewhat different from that described. For example, as has been men tioned, the guide section 53 may be greatly reduced or eliminated. The stop section 45 may be of other shapes, such as round. The sleeve may include the upper cylindrical section 47 as well as the camming section 45 of the tapered camming part. The construction of the rest of the nozzle, such as the location ofthe Venturi means or other parts may be varied considerably. These variations are merely illustrative.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

l. A fluid dispensing nozzle comprising a casing having an inlet and an outlet spout and a fluid passage therebetween, a main valve in said fluid passage, biasing means for biasing said main valve to a closed position, a manually operable lever for opening the main valve against the bias of said biasing means, and automatic shut-off means for disabling said manually operable lever in response to submersion of a part of said outlet spout, said automatic shut-off means including a plunger slidably mounted in said casing, means defining a pivotal connection between said lever and said plunger, an axial bore in the upper end of said plunger, a latch pin extending into said axial bore, said latch pin including a body part and a sleeve part rotatably mounted on said body part, said sleeve part including at least a tapered camming section, latching means in said plunger, said latching means being movable radially outwardly to a position for holding said plunger in a latched position and movable radially inwardly to release said plunger from said latched position, said latching means being engagable by said camming section of said latch pin to urge said latching means radially outwardly, a diaphragm supported in said casing to define a pressure chamber with said casing, aspirating means communicating with said pressure chamber, and passage means from said pressure chamber to said outlet spout for balancing pressure in the pressure chamber, and attachment means for securing said body part of said latch pin to said diaphragm for movement therewith.

2. The nozzle of claim 1 wherein said latching means include a plurality of radial openings in said plunger and balls in said openings, said openings communicating with said axial bore, said camming section of said latch pin being proportioned-to hold said ball radially outward of the adjacent outer surface of said plunger for engaging a cooperating latching shoulder in said casing, said plunger being nonrotatable about its lonitudinal axis when pivotally attached to said manually operable lever.

3. The nozzle of claim 2 wherein said attachment means for securing said latch pin body part to said diaphragm renders said latch pin body part nonrotatable about its longitudinal axis.

4. The nozzle of claim 3 wherein said latch pin also includes a retainer part, and wherein said latch pin body part includes, alongits longitudinal axis, a stop section, a spacer section of smaller maximum diameter than said stop section, a bearing section of smaller diameter than said spacer section,'and a yet smaller di ameter other section including means for carrying said retainer part, said sleeve part being rotatably mounted on said bearing section between said spacer section and said retainer. part, said sleeve part being tapered inwardly from said spacer section to said retainer part. 5. The nozzle of claim 4 werein said other section includes a transition section, said transition section being more severely tapered than said sleeve part, and. a

groove in said body part adjacent said bearing section, and wherein said retainer part comprises a snap ring carried in said groove.

6. The nozzle of claim 4 wherein said body part is made of a thermoplastic material and said sleeve part is made of a harder material than said body part.

7. The nozzle of claim 6 wherein said other section of said body part includes a retainer-carrying cylindrical section of smaller diameter than said bearing part, said retainer part being frictionally secured to said other section, said retainer part comprising at least a transistion section having a more severe taper than said sleeve part.

8. The nozzle of claim 7 wherein said other section also includes an elongate guide rod, said retainercarrying section connecting said guide rod to said bearing section.

9. A latch pin for use in an automatic high level shutoff system of a fluid dispensing nozzle, said latch pin comprising a body part, a sleeve part and a retainer part, said body part having a longitudinal axis of symmetry, attachment means at one axial end of said body part adapted to cooperate with second attachment means to secure said body to a movable part in said shut-off system, said body part further comprising, along said axis, a stop section, a spacer section of smaller maximum diameter than said stop section, a smaller diameter bearing section for rotatably supporting said sleeve part, and a yet smaller diameter other section including means for carrying said retainer part, said sleeve part being rotatably mounted on said bearing section between said spacer section and said retainer part, said sleeve part being tapered inwardly from said spacer section to said retainer part.

10. The latch pin of claim 9 wherein said other section includes a transition section, said transition section being more severely tapered than said sleeve part, and a groove in said body part adjacent said bearing section, and wherein said retainer part comprises a snap ring carried in said groove.

11. The latch pin of claim 9 wherein said body part is made of a thermoplastic material and said sleeve part is made of a harder material than said body part.

12. The latch pin of claim 11 wherein said other section of said body part includes a retainer-carrying cylindrical section of smaller diameter than said bearing section, said retainer part being frictionally secured to said other section, said retainer part comprising at least a transition section having a more severe taper than said sleeve part.

13. The latch pin of claim 12 wherein said other section also includes an elongate guide rod, said retainercarrying section connecting said guide rod to said bearing section.

14. The latch pin of claim 13 wherein said attachment means on said body part comprises an axial tap in said one axial end of said body part. 

1. A fluid dispensing nozzle comprising a casing having an inlet and an outlet spout and a fluid passage therebetween, a main valve in said fluid passage, biasing means for biasing said main valve to a closed position, a manually operable lever for opening the main valve against the bias of said biasing means, and automatic shut-off means for disabling said manually operable lever in response to submersion of a part of said outlet spout, said automatic shut-off means including a plunger slidably mounted in said casing, means defining a pivotal connection between said lever and said plunger, an axial bore in the upper end of said plunger, a latch pin extending into said axial bore, said latch pin including a body part and a sleeve part rotatably mounted on said body part, said sleeve part including at least a tapered camming section, latching means in said plunger, said latching means being movable radially outwardly to a position for holding said plunger in a latched position and movable radially inwardly to release said plunger from said latched position, said latching means being engagable by said camming section of said latch pin to urge said latching means radially outwardly, a diaphragm supported in said casing to define a pressure chamber with said casing, aspirating means communicating with said pressure chamber, and passage means from said pressure chamber to said outlet spout for balancing pressure in the pressure chamber, and attachment means for securing said body part of said latch pin to said diaphragm for movement therewith.
 2. The nozzle of claim 1 wherein said latching means include a plurality of radial openings in said plunger and balls in said openings, said openings communicating with said axial bore, said camming section of said Latch pin being proportioned to hold said ball radially outward of the adjacent outer surface of said plunger for engaging a cooperating latching shoulder in said casing, said plunger being nonrotatable about its lonitudinal axis when pivotally attached to said manually operable lever.
 3. The nozzle of claim 2 wherein said attachment means for securing said latch pin body part to said diaphragm renders said latch pin body part nonrotatable about its longitudinal axis.
 4. The nozzle of claim 3 wherein said latch pin also includes a retainer part, and wherein said latch pin body part includes, along its longitudinal axis, a stop section, a spacer section of smaller maximum diameter than said stop section, a bearing section of smaller diameter than said spacer section, and a yet smaller diameter other section including means for carrying said retainer part, said sleeve part being rotatably mounted on said bearing section between said spacer section and said retainer part, said sleeve part being tapered inwardly from said spacer section to said retainer part.
 5. The nozzle of claim 4 wherein said other section includes a transition section, said transition section being more severely tapered than said sleeve part, and a groove in said body part adjacent said bearing section, and wherein said retainer part comprises a snap ring carried in said groove.
 6. The nozzle of claim 4 wherein said body part is made of a thermoplastic material and said sleeve part is made of a harder material than said body part.
 7. The nozzle of claim 6 wherein said other section of said body part includes a retainer-carrying cylindrical section of smaller diameter than said bearing part, said retainer part being frictionally secured to said other section, said retainer part comprising at least a transistion section having a more severe taper than said sleeve part.
 8. The nozzle of claim 7 wherein said other section also includes an elongate guide rod, said retainer-carrying section connecting said guide rod to said bearing section.
 9. A latch pin for use in an automatic high level shut-off system of a fluid dispensing nozzle, said latch pin comprising a body part, a sleeve part and a retainer part, said body part having a longitudinal axis of symmetry, attachment means at one axial end of said body part adapted to cooperate with second attachment means to secure said body to a movable part in said shut-off system, said body part further comprising, along said axis, a stop section, a spacer section of smaller maximum diameter than said stop section, a smaller diameter bearing section for rotatably supporting said sleeve part, and a yet smaller diameter other section including means for carrying said retainer part, said sleeve part being rotatably mounted on said bearing section between said spacer section and said retainer part, said sleeve part being tapered inwardly from said spacer section to said retainer part.
 10. The latch pin of claim 9 wherein said other section includes a transition section, said transition section being more severely tapered than said sleeve part, and a groove in said body part adjacent said bearing section, and wherein said retainer part comprises a snap ring carried in said groove.
 11. The latch pin of claim 9 wherein said body part is made of a thermoplastic material and said sleeve part is made of a harder material than said body part.
 12. The latch pin of claim 11 wherein said other section of said body part includes a retainer-carrying cylindrical section of smaller diameter than said bearing section, said retainer part being frictionally secured to said other section, said retainer part comprising at least a transition section having a more severe taper than said sleeve part.
 13. The latch pin of claim 12 wherein said other section also includes an elongate guide rod, said retainer-carrying section connecting said guide rod to said bearing section.
 14. The latch pin of claim 13 wherein said attachment means on said body part compRises an axial tap in said one axial end of said body part. 